The process of manufacturing electronic components, for instance, the process of manufacturing display substrates, generally comprises the step of drying glass substrates in a drying oven. During the transmission of glass substrates by a robot, when interactive signals are disconnected due to the alarm of the robot or the oven, the inaccurate value of the amount of the number of glass substrates existing in the drying oven tends to occur. For instance, in the case where the robot takes out an substrate (substrates) while the alarm of the robot occurs at the same time, the robot does not act due to signal interrupt (namely there is no sheet taken out of the oven and therefore the oven is still kept in the full-sheet state), but the existence value of the number of glass substrates in the oven will be reduced by a corresponding amount of the glass substrate(s) in response to the action of the robot, and hence an inaccurate count of the existence value of the number of glass substrates in the oven will occur. At this point, if a processor starts a device without confirming the condition of inventories in the oven, the device will wrongly determine that the existence value of the number of glass substrates in the oven is less than the maximum filling value of the glass substrates in the oven, and hence the robot will continuously transmit the glass substrates into the oven, and consequently the risk of breakage will be greatly increased.
At present, the phenomenon of sheet breakage in the oven is usually prevented by the mounting of a sensor, but the cost is relatively high. Taking the one drop filling (ODF) technology as an example, the cost of mounting the sensor is approximately RMB 720,000 for each production line, and hence the cost is too high.